Tudy On Data Transferring Technologies In Network Navigation Services

With correlative technology develop rapidly, the request and service mode has been changed profoundly in NNS(Network Navigation Services). Server cluster can integrate the data from different departments and resolve them on network, satisfying the user Navigation requirement mostly. The Server cluster can combine the mode of raster data and vector data to express the geography space data, and transmit these data on different grades and parts; While user can convey their requirements to the server via multi-approach, for example by Web, by wireless network, SMS/MMS and so on. Similarly users can enjoy the NNS by the same approaches.Sum up, this paper studies from following:1. The rise of the mode of NNS requirement diversified, users can convey their query to server cluster by Web, wireless network, SMS/MMS and so on. But the query content still singleness, always we use the key words or attribute to achieve it. The server cannot afford the picture information resolve, geo-space data analysis, so the fuzzy query capability is poor, user interactive experience is not friendly.2. In this paper we have discussed the data transmission elements in NNS, the mode of navigation service, the data transmission flow between the user and the server cluster. And summarize the hot technology: Agent, Ajax.3. NNS need geography data sustain deeply. The paper has discussed the advantage and limitation between raster data and vector data. They complement one another, so we suggest use raster data and vector data in NNS at the same time.4. We has design the NNSOntology formalization method, Agent body, constructed the SVG data transmission system based on Agent; the raster data display, user Web query system, mobile terminal receive MMS experiment.The innovation of this paper includes:1. For the problem of database heterogeneity in the mode of SMS/MMS requirement, we shield the difference between database heterogeneity and platform by using regular command mapping forms based on XML.2. As we know, the raster data is not precision, the vector data has heterogeneity problem in transmission, so this paper suggest use the raster data and vector data in NNS at the same time. Which one has the complex topological relation, abundant map information will be realized by the raster data, while the dynamic regenerative navigation data will be transmit to user in the vector data form.3. For the vector data has heterogeneity problem in transmission, we suggest adopt the SVG data format as the vector data form network transmission, shield the difference between database heterogeneity.4. Takeing the problem of internet environment is not optimization into account, this paper utilizes the multi-agent system advantage in distribute environment, Ajax asynchronous transmission mode to improve the data transmit stability. Give the user friendly Interactive experience.